I. Field
The present disclosure relates generally to electronics, and more specifically to multi-carrier transmitters.
II. Background
A wireless device (e.g., a cellular phone or a smartphone) in a wireless communication system may transmit and receive data for two-way communication. For example, the wireless device may operate in a frequency division duplexing (FDD) system or in a time division duplexing system (TDD). The wireless device may include a transmitter for data transmission and a receiver for data reception. For data transmission, the transmitter may modulate a radio frequency (RF) carrier signal with data to obtain a modulated RF signal, amplify and filter the modulated RF signal to obtain an amplified RF signal having the proper output power level, and transmit the amplified RF signal via an antenna to a base station. For data reception, the receiver may obtain a received RF signal via the antenna and may amplify, filter and process the received RF signal to recover data sent by the base station.
A wireless device may support operation over a wide frequency range. The wireless device may include a number of amplifiers, with each amplifier being designed to operate over a portion of the wide frequency range supported by the wireless device. For example, the wireless device may operate in a carrier aggregation (CA) communication system in which the device comprises multiple uplink (UL) transmitters transmitting at different carrier frequencies. However, simultaneous transmission by the transmitters might cause receiver desensitization due to intermodulation distortion (IMD).
Therefore, it is desirable to have a distortion canceller for use in a wireless device to support operation over a wide frequency range while reducing intermodulation distortion.